Support for Mexican presidential hopeful Josefina Vazquez Mota, candidate of the ruling National Action Party (PAN), has fallen to its lowest level since the campaign began at the end of March, a poll showed on Tuesday.

Vazquez Mota's efforts to win the July 1 election have been undermined by public discontent with President Felipe Calderon's administration over rampant drug-related violence which has claimed some 55,000 lives since the start of 2007.

The PAN has also struggled to create enough jobs to cater for Mexico's growing population.

Support for Pena Nieto, 45, the telegenic former governor of the State of Mexico, inched down a tenth of a point to 38.4 percent, according to the latest Mitofsky poll, which was conducted between May 11 and 13.